Entities with substantial printing demands typically implement a high-speed production printer for volume printing (e.g., one hundred pages per minute or more). Production printers include continuous-forms printers that print ink or toner on a web of print media stored on a large roll. An ink jet production printer typically includes a localized print controller that controls the overall operation of the printing system, and a print engine that includes one or more printhead assemblies, where each assembly includes a printhead controller and a printhead (or array of printheads). An individual ink jet printhead typically includes multiple tiny nozzles that discharge ink as controlled by the printhead controller. A printhead array is formed from multiple printheads that are spaced in series across the width of the web of print media.
While the ink jet printer prints, the web is quickly passed underneath the nozzles, which discharge ink onto the web at intervals to form pixels. A dryer, installed downstream from the printer, may assist in drying the wet ink on the web after the web leaves the printer. In an electrophotographic production printer, the imaged toner is fixed to the web with a high temperature fuser. Handling the web can prove challenging due to variation of a number of factors.
One such factor occurs when the printer stops printing, at which time curling and browning of the web around small diameter, high temperature rollers may occur. Rollers attain high temperature either directly from heaters or indirectly such as from contact with a heated web. A web engaged in a dancer roller mechanism is susceptible to this issue. Dancer rollers mechanisms may be used at various points in a web handling system in order to buffer the web or maintain web tension despite the different web handling characteristics (e.g., speed variations, acceleration and deceleration profiles) of the different pieces of web handling equipment that compose a web handling system. Dancer roller mechanisms can also be used to cool the web, such as by exposing the web to cooling airflow or through chilled rollers. Existing external dryers may include a dancer roller mechanism on the exit end of the dryer to buffer the web, maintain tension and cool the web during printing. However, the dancer roller mechanism does not address the curling or browning issue when printing stops.
Accordingly, a curl resistant web handler is desired.